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Re: [Condor-users] scaling problems with condor_negotiator

Matt Hope wrote:

On 2/28/07, Smith, Ian <I.C.Smith@xxxxxxxxxxxxxxx> wrote:

Does the negotiator treat a cluster as a single entity since all its
component process have the same requirements hence putting a smaller
load on it (I moved from cluster to individual jobs with the wrapper

Been on holiday so only just seen this.

In 6.6 condor can treat clusters differently by considering a false
result for one job/node pair in a cluster a false result for that node
with the entire cluster (with a massive performance boost to
negotiation if enabled and clustering is heavily used).

The new features trialed in later 6.7 releases and added by default in
6.8 attempt to make such manual intervention unnecessary but I can't
remember off the top of my head if they still rely on clustering for
maximum benefit.

In 6.8, the thing to look at is how well your jobs are getting "auto clustered". This auto clustering happens, for the most part, behind the scenes and helps improve the efficiency of negotiation by grouping equivalent jobs together.

You can see how the jobs are getting grouped together by looking at the job attribute AutoClusterID. Example:

condor_q -f "%s" ProcID -f ".%s" ClusterID -f " %s\n" AutoClusterID

Jobs with the same AutoClusterID are in the same group for negotiation purposes. If you see that many small groups are being created, take a look at the attribute AutoClusterAttrs. This will tell you what attributes are being used to group jobs together. All jobs in a group have identical values for these attributes. In some cases, it may be necessary to tweak the way a particular attribute is being rounded. See SCHEDD_ROUND_ATTR in the manual for more information on that: